The present invention relates to gaseous mixers for introducing gaseous fuel (i.e., fuel that naturally exists in a gaseous state, rather than a liquid state) and recirculated exhaust gas into an intake passage of an internal combustion engine, for example in a passenger vehicle. Gaseous fuels include natural gas (primarily methane) and derivatives thereof, such as butane and propane, but do not include gasoline.
Natural gas can be used to power internal combustion engines. Compared to conventional engines, vehicles run on natural gas are fuel-efficient and environmentally friendly. They are also able to provide good torque and robust performance, while outputting less engine noise than traditional diesel-powered engines. However, in order to meet the needs of a variety of different engines with varying displacement, performance, etc., a high number of specialized parts are required.
Modern natural gas engines employ Exhaust Gas Recirculation (EGR) to provide various performance benefits, including improved efficiency, increased torque, and reduced emissions compared to engines without EGR. The introduction and mixing of fuel and recirculated exhaust gas with intake air require separate devices.